In 2008, 10 million tons of natural rubber, cis-1,4-polyisoprene, will be produced for commercial use. Every molecule of that product will be produced in a microscopic bioreactor known as the rubber particle. These particles, suspended in an aqueous phase called latex, evolved to produce and store natural rubber in plants. Their robust nature allows them to be exploited by industry once the particles have been harvested from the plants. Through studies of the chemistry and biology of rubber particles, a more detailed understanding of this dynamic and complex bioreactor system is emerging.